Method and apparatus for manufacture of electrodes



June 29, `1965 A. L. CROSBY ETAL METHOD AND APPARATUS FOR MANUFAGTURE OFELECTRODES INVENTORS Amm L. Casar, M4K/afl DeL um. .Sr/mfr J Gar/vn d?#Maw D. Lash ATTORNEY v June 29, 1965 A. n.. cRosBY ETAL 3,191,637

METHOD AND APPARATUS FOR MANUFACTURE OF ELECTRODES 11 Sheets-Sheet 2 BYL4/ff TTORNEY June 29 1955 A. l..A cRosBY ETAL 3,191,637

* METHOD AND APPARATUS FOR MANUFACTURE OF` ELECTRODES Original FiledNov. 2', 1959 1l Sheets-Sheet 5 'ATTQRNEY June 29, 1965 A. l.. CROSBYETAL 3,191,637

METHOD AND APPARATUS FOR MANUFACTURE 0F ELECTRODES Original Filed Nov.2, 1959 l1 Sheets-She/t 4 Fil;- 4

RNEY

June 2 9, 1965 A, CROSBY ETAL 3,191,637

METHOD AND' APPARATUS FOR MANUFACTURE 0F ELECTRODES original llednov.2A, 1959 11 Sheets-Sheet 5 *7 El dglllnllv////////////////////////ALL 7/52 u WM f4 ,t j @qu f INVENTORS ALraNL, Mu Mmm/5. DfLuc/A,STANg-YBJYGAm-Mu l Ham n D. Las: y

June 29, 1965 A, L. cRosBY ETAI.v .3,191,637

METHOD ANDV APPARATUS FOR MANUFACTURE 0F ELEcTRoDEs 11 Sheets-Sheet 6Original Filed Nov. 2, 1959 f.../ M m m m F f l M .1.. 4\ m. m::. f ..2m a Q www, n. 6 mam O O m mw mi om l o o mm1. o o G f 4 am., J 1. x um/.www w lNVENToRs ,4L raw L. Ckassy, Maf/0N 5. DA'L ucm,

JTBQIAHMH d 166410.42) aser June 29, 1965 A, L. cRosBY ETAM.` 3,191,637

METHOD AND APPARATUS FOR MANUFACTURE oF ELEcTRoDEs A Original Filed Nov.2, 1959 11 Sheets-Sheet 7 Q@ Y 47 oo l ATTORNEY June Z9, 1965 A. L.CROSBY ETAL 3,191,637

METHOD AND APPARATUS FOR MANUFACTURE OF ELECTRODES original Filed Nov.2, 1959 l1 Sheets-Sheet 8 l' Wj 'EDF-11144535 j 49a :D 50a l E "VI /506l 5" 504m" 502 l 5M,- .f5/2

INVENTORS A/.ra/vl. Oxosy, MAR/(W6. DiL ucm,

June 29, 1965 A. l.. cRosBY ETAL 3,191,637

METHOD AND APPARATUS FOR MANUFACTURE OF ELECTRODES Original Filed Nov.2, 1959 11 Sheets-Sheet 9 11 Sheets-Sheet 10 A. l.. CROSBY l-:TAL

June 29, 1965 METHOD AND APPARATUS FOR MANUFACTURE OF ELECTRODESOriginal Filed Nov. 2, 1959 Fi@ 55 M El@ E 7 June 29, 1965 A, L CROSBYETAL 3,191,637

METHOD AND APPARATUS FOR MANUFACTURE OF ELECTRODES 11 Sheets-Sheet 11Original Filed Nov. 2, 1959 .WY Sw SSE W mm m m SE l Y @m Sum. maw M S mmm m d www. m G SMQ ffm S www QG am 2% .QQ MM m M my m Sm 2S UnitedStates Patent O 3,191,637 METHD AND APPARATUS FR MANUFACTURE FELECTRODES e Alton L. Crosby, Austin, and Marion S. De Lucia, Stanley J.Gartner, and Harold E). Losey, Emporium, Pa., assignors to SylvaniaElectric Products inc., a corporation of Delaware Original applicationNov. 2, 1959, Ser. No. 850,407. Divided and this application May 14,1962, Ser. No. 194,629

S Claims. (Cl. 140-71.5)

The present invention is a division of Serial No. 850,407, tiledNovember 2, 1959,` and assigned to the same assignee as the subjectapplication. i

This invention relates generally to the manufacture of electrodes foruse in electron discharge devices and more particularly to a method andapparatus for the manufacture of grid electrodes.

Electron discharge devices generally comprise a plurality of electrodesarranged in spaced relation to one another. The operatingcharacteristics of such devices are related to and controlled in part bythe configuration of the internal electrode structures and by theaccuracy or precision with which such structures are fabricated. Thegrid electrodes are particularly critical since certain importantcharacteristics, for example, tube transconductance and noise level, areclosely related to the size and spacings of the lateral grid wires whichtraverse the electron path. The spacings and configurations of the gridlateral wires is important not only with respect to each other but alsowith respect to the position of other electrodes in the assembly.

In relatively low frequency tube applications it is possible to uselateral wires of suiicient cross-sectional area and strength to be atleast partially self-supporting. In this case the lateral Wire spacingis such that each turn of the helix of lateral wire could be aiixed tothe side rods. High frequency tube applications, however, require a highnumber of turns per inch of extremely fine lateral wire. Lateral Wiresof this size are normally too Weak to be used in the previously employedmica-supported side rods structures. It is therefore necessary that anaccurately fabricated rigid grid frame be employed. Further, the highnumber of turns per inch required prevents the use of conventionalmethods for securing the tine lateral wire to the side rod such as bynotching and swaging.

The smallness of the electrodes and their close spacing within thecompleted device increase the heat dissipation problem and require theutilization of materials having high temperature-strengthcharacteristics for the side rods and lateral wires. Use ofhard'materials such as molybdenum for the side rods and tungsten for thelateral Wires normal-ly creates intense problems of tool wear and thelike, where the lateral wire helix is continually secured to the siderods of the grid supporting structure.

To overcome these problems the prior art suggests the use of theself-supporting frame upon which fine lateral grid wires are closelywound and continuously attached to the side of the frame by hightemperature bonding techniques such as welding or brazing, or by the useof a fusable material such as glass frit.

From an electrical viewpoint, the grid electrodes made in accordancewith the prior art suggestions appear to function satisfactorily;however, to date, the desired electrical characteristics have beenpurchased at a high cost resulting from a lack of manufacturing controland automatic fabricating apparatus and techniques. Thus it is an objectof this invention to facilitate manufacturing control and automaticproduction of frame-type grid electr-odes having a relatively largenumber of laterals per unit length of grid opening.

ICC

It is another object of this invention to facilitate the production offrame-type grid electrodes made from materials having hightemperature-strength characteristics such as molybdenum and tungsten.

It is Vyet another object of this invention to improve the process ofwinding grid laterals about a rigid frame.

It is a further object of this invention to provide apparatus for theproduction of frame-type grids employing extremely fine lateral wire.

Briefly, in one aspect of the invention, an apparatus s provided forwinding closely spaced turns of grid lateral -wire about a frame whichemploys means for rotatively supporting a grid frame, means forsupplying the lateral wire, means for securing the lateral wire to thegrid frame, means for producing relative movement between the lateralwire supply means and the grid frame support to feed the lateral wirealong the frame while the wire is being wound on the rotating frame, andmeans for securing the lateral wire to the frame at the completion ofthe winding operation. The lateral wire is thus secured to the frameonly at the beginning and end of the helix. The lateral wire ismaintained in position intermediate the secured ends of the winding -bythe frictional engagement of the lateral wire, under tension, and theside rods.

A typical grid which may be fabricated according to the teachings ofthis invention has a major of .158 inch, a minor of .0315 inch and isWound with 354 turns per inch of tungsten Wire having a diameter of.0003 inch for a distance of .305 inch. The frame employs molybdenumside rods having a .0315 inch diameter.

For a better understanding of the invention reference is made to thefollowing description taken in conjunction with the accompanyingdrawings in which:

FIG. 1 is a plan view of the apparatus with some parts broken away andother parts in partial section showing the general arrangement of theapparatus;

FIG. 2 is a side elevation of the apparatus of FIG. l;

FIG. 3 is an enlarged front elevational view of a portion of theapparatus showing the rotatively driven spindle;

FIG. 4 is a side elevation of a portion of the spindle mechanism takenalong the line 4-4 of FIG. 1;

FIG. 5 is a cross section of a portion of the spindle mechanism takenalong the line 5 5 of FIG. l;

FIG. 6 is a plan view of a grid manufactured on the apparatus shown inFIG. l;

FIG. 7 is a perspective View of the frame employed in the production ofthe grid shown in FIG, 6;

FIG. 8 is an elevation and partial section of the winding and supportspindles shown with a frame prior to threading onto the mandrel;

FIG. 9 is an end view of the supporting spindle taken along the line 9 9of FIG. 8;

FIG. 10 is an end view of the mandrel and winding spindle taken along aline itl-#10 of FIG. 8;

FIG. l1 is a front elevation similar .to FIG. 8 showing the grid framelthreaded ont-o the mandrel;

. FIG. 12 is a plan view similar to FIG. `11;

FIG. 13 is a view in section of the frame in position on the Windingmandrel taken along the line 1-3-13 of FIG. 11;

FIG. 14 is an elevational view of the apparatus taken along the line1414 of FIG. 1;

FIG. 15 is an end view elevation of .the apparatus taken along the line15-115 of FIG. 1;

FIG. 16 is a rear elevation of the apparatus taken along thevlinel16-.16 of FIG. 1;

FIG. 17 is a front elevation of the apparatus showing the Vcam feed for-the lateral wire supply;

FIG. 18 is a partial elevational view taken from the 3 side showing thereturn means for the feed cam of FIG. 17;

FIG. 19 is a plan view showing the wire threader, wire guide andclamping means;

lFIG. 2O is a rea-r elevation of the wire threader of FIG. 19;

FIG. 2l is a sectional view taken along the line 21-21 of FIG. 17;

yFG. 22 is a cross-sectional view in elevation taken along the line22-22 `of FIG. 1;

FIGS. 23-28 are sequential operational views of the produotionof gridson the apparatus of FIG. 1; l

l FIG.` 29 is a timing chart indicating periods during which various camoperated means function; land FIG. 30 is a representation of the spindlemotor speed vs. position of .the'lateral wire feed means along theleng-th of the grid winding.

Referring to FlGS. l, 6 and 7, in one embodiment of theY invention, anapparatus is provided for winding closely spaced turns of `lateral wire160 about a grid frame 102 comprising in combination, means 184 forrotatively supporting the grid frame, means 106 for supplying thelateral wire, means 168 for securing the lateral wire to the grid frame,means 1 1() for producing relative movement between the lateral Wiresupply means 106 and the grid frame support means 104 to feed thelateral wire 100 along the frame 102 while the wire is being wound onthe frame, and means 112 for securing the lateral wire to the frame atthe completion of the winding operation. The various means are arrangedin operative relation on the apparatus frame 114.

Grid frame The grid frame 102, upon which a helix of lateral wire 100 isto be wound, is formed from a pair of side rods 116, 117 which areconnected together by lirst 118 and second 120 pairs of strap members.The straps may be secured to the siderods by conventional means such asWelding. The lateral wire 100 is secured to the frame at the start 122of the helix and at the termination 124 of the helix.

In the embodiment of the invention illustrated in the drawings the frame102 has been fabricated prior to the Winding operation. FIG. 6illustrates a completed grid wherein the frame length between the straps118, 120 is wound with a uniformly pitched helix of lateral wire. Gridshaving only a portion of their length may also be fabricated on thisapparatus as well as grids having variable pitch as required for use incertain electron discharge devices.

Winding mandrel and spindles The grid frame 102 is supported on. amandrel 126 during the winding operation. The winding mandrel, 126,closely approximates the interior configura-tion of the frame, beingprovided with semicircular grooves 128 to accommodate the side rods 116.The straps 120 abut a shoulder 130 formed on the mandrel when the frame132 is threaded on the mandrel. The free end 132 of the mandrel has ataper formed thereon to expedite the loading of the frame. This taperalso assists in centering and supporting the mandrel during thesubsequent operations. Mandrel body 134 is provided with grooves inwhich the stripper pins 138 pass to remove the completed grid. Themandrel body 134 is mounted in a Vcavity 140 in a rotatively drivenspindle 142. The tapered free end 132 of the mandrel 126 is supported bya receptor 144 held in a socket 146 in a second rotatively drivenspindle 148 when-the mandrel is advanced to Ithe winding'position at theworkstation. This receptor is provided with a recess 150 in its free endin which the tapered mandrel end 132 is supported. A shoulder 152 on thereceptor abuts the frame straps 118 to retain the frame in position onthe mandrel.

Referring to FIGS. 1, 2 and 3, therotatively driven spindle 142 isslideably supported for longitudinal movement by bearings 154 in theapparatus frame 156. A gear 158 is axed to the spindle, intermediate thebearings 154, in operative relation with an idler gear 160 mounted onshaft 162 which is journaled in the apparatus frame. The idler gear 161)in turn meshes with the spindle drive gear 164 aixed to the spindledrive shaft 166. The dn've shaft 166 is supported by bearings 168 afxedto the platform 114. Variable speed spindle drive motor 170 rotates thespindle drive shaft through a belt 172 running between a pulley 173 onthe spindle drive shaft 166 and a pulley 174 on the motor shaft. Fluidpressure operated clutch 175 is interposed between Ithe pulley 173 andthe shaft 166 and is connected by conduit 176 to a fluid pressuresource, not shown. The second or xed spindled148 is driven by thespindle drive shaft 166 through drive gear 178 aixed to the drive shaft,a frame supported idler gear `1813*, and a gear 182 aixed to `thespindle l148. The rotation of the spindles is synchronized since theyare driven from a single shaft 1 66. Cam stops A and B, which includecams 183, 18,4 :that are controlled by solenoids 185, 186 respectively,are affixed to the shaft 166 (see FIG. 15). Each of the ,cams 183, 18.4is provided with a notched portion 187 into which a frame mounted springloaded pivot arm 188 is moved to stop the rotation of the shaft 166 in apre-selected position. The cam stops are each operated independently ina similar manner. The operation of cam stop A is controlled by solenoidwhose armature 190 is coupled to the lever arm 188. When the solenoid185 is energized it will move the arm 188 out of the notch 187 thusreleasing the shaft 166 for rotation. The armature of solenoid 186 whichOperates cam stop B performs an additional function in that it operatesa switch 192. Solenoids 185, 186 are mounted on a bracket 193 affixed tothe apparatus frame 114. During the grid notching, winding and plowingoperations the movable winding spindle 142 is additionally supported bya yoke 194 lallixed to the apparatus frame..

Referring to FIGS. 1, 3 and 4, reciprocation of the winding mandrel 142from a retracted loading position to the advanced winding position atthe workstation is produced by the operation of fluid motor 195. The ram196 of the motor 195 is attached to the spindle 142 by a bearingconnection 198 which allows the spindle to rotate while the ram isrestrained from rotating. Pin 200 aflixed to the ram operates threeuni-directional limit switches 262, 204, 206 when the ram isreciprocated and prevents the rotation of the ram. These limit switchesare all of the one way momentary contact type. The pin 200 passesthrough a slot 208 in the mounting bracket 210A on which the switchesare adjustably positioned.

Stripper mechanism Referring to FIGS. 1, 3, 5 and 11 the stripper pins138 are secured at one end to a block 212 slideably contained within thewinding spindle cavity 140. Stripper rod 214 is connected to the block212 by a pin 216.` The rod 214 Iterminates in a communicating interiorcavity 218 of the spindle 142 (see FIG. 3). Stripper rod 214 is retainedin position by a pin 222 which passes through slots 224 in the spindle142. The return spring 226 retracts the stripper rod 214 when the pin222 is released. The stripper pins 138 are actuated when the spindle 142is retracted by a stripper bar 231) aliixed tothe ram 232 of the fluidmotor 234 (see FIGS. 1 and 5). In its advanced position the bifurcatedstripper bar 230 contacts the pin 222. The stripper bar 230 ispositioned by the cooperation of an ear 236 on the bar and a slot 2138formed in the guideplate 240.

N Olching mechanism In the type of grid illustrated in FIG. 6, thelaterallateral wire portion in the notch to anchor it in place (see FIG.28)

The notches 242, 244 are formed at the workstation by a mechanismindicated generally at 245 of FIG. 3. Referring to FIG. 24, the notchingtools 246, 248 are identical, each being formed with one verticalsurface 250 and an inclined cutting surface 252 to produce the notchshown. Other notch configurations can be produced, as desired, bychanging the contour of the notching tools.

The notching tools 246, 248 are adjustably mounted on the upper end of aslide 254 (see FIGS. 3, 14) which is reciprocated in a slide way 256supported bythe apparatus frame 156. The position of the tools may beindividually adjusted with respect to the grid frame 102. Reciprocationof the slide 254 is produced by the movement of a cam driven lever arm258 having a bifurcated end 260 which slidably straddles a block 262pivotally mounted on an L-shaped pivot arm 264. The arm 264 is itselfpivotally mounted on the slide 254 about a pin 266. Position of thepivot arm 264 is controlled by an adjustable stop 268 carried by a plate270 secured to the slide 254 and a spring 272 positioned between thelever arm 264 and a second plate 274 carried by the slide. Operatinglever arm 253 is rocked about its pivot 276 by the action of therotating notching tool cam 27S against cam follower 279 attached to thelever. The cam 273 is affixed to the lower cam shaft 280 which is driven(see FIG. 1) by gear motor 282 through a sprocket 284, chain 286 andsprocket 288 mounted on a shaft extension 290. Fluid pressure operatedclutch 292 is interposed between the :shaft extension 290 and the cameshaft 280 proper. The cam shaft 280 is rotatably supported by bearings294 adjacent its ends and makes one complete revolution per grid.

Means for producing relative movement Referring to the drawings, FIGS.1, 15 and 16, the means 110 for producing relative movement between thelateral wire supply means 106 and the grid frame support means 104derives its motive power from spindle drive shaft 166. A miter gear 296on the spindle shaft 166 engages a gear 298 on shaft 300 which issupported by bearing members 302, 304. A gear 306 affixed to the end ofshaft 300 meshes with an idler gear 308 mounted on shaft 310 which ispositioned by bracket 312. VIdler gear 303, in turn drives gear 314attached to the input shaft 316 of a geared speed reducer 318. Gear 320is affixed to the output shaft 322 of the reducer 318 and engages achange-gear train indicated generally at 324. The various gears in thetrain are arrayed on brackets 326 affixed to the apparatus and may beinterchanged or replaced to vary the input to output ratio of the geartrain. The output gear 328 of the train 324 is secured to a hollow shaft330 which terminates in a fluid pressure operated clutch 332. The clutch332 selectively connects shaft 330 with shaft 334 when energized.Friotion brake 336, mounted on bracket 338, restrains the movement ofshaft 330 to reduce the backlash incident to the use of change geartrain 324. The clutch 332 is connected to a source of uid pressure (notshown) through the shaft 330 by means of a conduit 340. Shaft 334 issupported by bearing members 342, 344 adjacent its ends.

Cam stop C (FIG. 16) has a cam 346 similar to cam 183 of cam stop A,previously described, secured to the shaft 334. The spring loaded stoparm 343, solenoid operator 350 and a solenoid armature operated switch352 are mounted on bracket 193. 'Timing cam 354 is also affixed to thesame shaft 334 and operates a switch 356 on bracket 193 when rotated bythe shaft. Speed control serv-o potentiometer 358 for the spindle motordrive 170 -is positioned on a bracket 360 above the shaft 334 and isconnected thereto by a sprocket 362 on the shaft 334, sprocket chain 364`and sprocket 366 on the potentiometer.

The feed cam return motor 363, whose function will lbe discussed later,is mounted on the platform 114 and connected to the shaft 334 through anover-running clutch 370, sprocket 372, chain 374, and sprocket 376mounted on friction clutch 378 which is secured to the shaft 334 (seeFIGS. 16, 18). The over-running clutch 370 comprises a body por-tion 380secured to the return motor shaft 382, a pawl arm 384 pivotally .aflixedto the body 330, a spring 336 between the arm and the body, and aratchet wheel 388 aflixed to the sprocket 372. The 'sprocket 372 is freeto rotate on the shaft 382 in yone direction but the ratchet Wheel 338engages the pawl arm 384 when the sprocket is oppositely driven. Thefriction clutch 373 allows the `sprocket 376 to rotate when driven whilethe shaft 334 is held against rotation by cam stop C.

Referring to FIGS. l, 15 and 17, Wire feed cam 390 is adjust-ablymounted on a collar 392 which is affixed to the end of shaft 334. Theedge contour of the cam, which makes one revolution per grid, determinesthe movements of the wire supply slide 394 through a cooperating camfollower 396 affixed to the slide by arm 393. The cam periphery includesa rapid ch-ange in contour shown here as a notch 400 which is used toproduce a more rapid than normal movement of the slide 394.Approximately 270 degrees of the cam periphery is used for positioningthe lateral wire longitudinally along the frame during the wind-ingoperation, and the remainder is used to return the slide 394 t-o itsstarting position. The slide moves on a fixed shaft 402 which passesthrough bearing bosses 434 and 406. The shaft 402 is attached to arms40S, 410 of bracket 412 which is affixed to the apparatus frame. Camfollower 396 is held .against the cam 390 by a spring 414 mounted aboutthe fixed shaft 402 between the boss 46.6 on the slide and .arm 408 onthe bracket 412. Slide 394 is prevented from rotating about the fixedshaft 402 by a pair of rollers 416, 413, ailixed to an extension of theboss 404, which straddle a guide rail 420 on the bracket 412.

Lateral wire supply Referring to FIGS. 1, 2, 14, 17 and 19, the lateralwire supply means 106 is mounted on wire supply slide 394 by a supportpedestal 422 which is aflixed to a transverse member 424 secured to theslide. A spool 426 Iof lateral Wire is removably attached to and carriedby a drum 428 on shaft 430 which is journaled in one end in the pedestal422 and at the other end in a removable member 432. A friction brakewheel 434 is secured to the shaft 430 .adjacent the drum 423. `Brakelever 436 carrying felt pad 438 is pivoted at 440 -on .the pedestal. Thefelt pad is pressed against the wheel 434 by a spring 442 which reactsbetween a set screw 444 on the pedestal and the brake lever 436 abovethe pivot point of the lever. Set screw 444 enables adjustment of `thedegree of retardation of the rotation of the wheel 434 and hence .thespool 426 of lateral wire on the drum. In this manner the tension on thelateral wire, as it is drawn olf the spool during the winding operation,may be adjusted. The aforementioned structure allows the exchange of afull spool for an empty spool to be performed easily.

Wire guide and clamping means It is necessary that the lateral wire 100be positioned accurately on the grid frame 102 during the windingoperation to insure the production of a satisfactory grid. In order toplace the Wire 100 in its proper position a Wire guide means 446 isprovided. The guide comprises a fixed finger or jaw 443 and a movablelinger or jaw 450 (FIG. 19). Each of the fingers is provided with anextension 452 (see FIG. 14). The horizontal movement of the lateral wire13b is limited when it passes between the slightly separated unclampedextensions 452 but it is free to move vertically. Operating means 454are provided to clamp the wire 100 in place between the extensionsalumna 452 as required by the operation of the apparatus. The fixed:linger 448 is secured to the body 456 `of the clamping means 454 whichis adjustably mounted on the transverse member 424 ,carried by the slide394. The movable dinger 450 is secured to a block 458 slidable beneath acover plate 468 within the clamping means 454 (FIG. 2l). Block 458 iscaused to shift and thereby cause the wire 10i) to be clamped orreleased between `the ex- .tensions 452, by the application of the iluidpressure through a bushing 462 axed to the side plate 484. The bushing462 is connected at one end to a s-ource of iluid pressure .(not shown)by a conduit 466. The other end of the bushing 462 extends into achamber 468 formed in the block 458. An O-ring 478 on the bushing 462effectively prevents loss of fluid pressure. The block 458 is normallybiased to an unclamped position by a spring 47-2 contained in a recess474 in the block 458. The spring reacts between the block 458 and thefixed nger 448. Therefore, when fluid pressure is yapplied through thebushing 462 the block 458 will be moved closing the gap between theextensions 452 of the fingers 448,458 and clamping the lateral wire 180therebetween. The wire is guided over the body 456 of the clamping meansby a member 476 affixed to the stationary portion of the clamoing means(FIG. 14).

Lateral wire vibration damper A lateral wire vibration damper 478-(FIGS. 1, 14, 19) is mounted on the body 456 of the wire guide clampingmeans 446 to reduce the vibration induced in the lateral wire 188 whilebeing wound on the rotating grid frame y162. The damper 478 includes areed-like member 488, preferably metal, mounted at one end on aninclined support block 482. A felt pad 484, which is normally in contactwith the lateral wire 10G, is affixed to the other end of the reed 488.The damper 478- is tuned to reduce the vibration of the wire 108 whichwould otherwise cause mis-spacing at certain winding speeds. Thefrequency of the oscillation induced in the lateral wire is dependentupon the rate of rotation of the frame or winding speed.

Lateral wire threading means Lateral wire threading means 486 areprovided to position the lateral wire 180 in the first notch 242 formedin the side rod 116. Referring to FIG. 19, the threading means 486includes a xed finger or jaw 488 and a movable finger or jaw 498, eachprovided with a vertical extension 492. Relative movement of the tingersis provided by a fluid pressure operated clamping means 494 similar inconstruction to the clamping means 454 used to operate the wire guidemeans 446. In the drawing (FIG. 19), the cover plate has been omitted sothat the bushing 462 and block 458 may be seen. Fluid pressure issupplied to operate the clamping means through a conduit 486.

The clamping means 494 is adjust-ably aliixed to a slide 498 (FIGS. 14,20). Slide 498 is carried by a platform 588 which is mounted on one endof a reciprocatable shaft 582. The slide 498 is maintained on theplatform 580 by gibs 584, 586 attached thereto. Shaft 581 is supportedfor reciprocatory movement by bosses 502, Si@ which are formed as partof a support bracket 512. The bracket 512 is secured to the apparatusframe adjacent the spindle drive shaft 166, for which clearance groove514 is provided. Reciprocation of the shaft 582 is produced by wirethreader lift cam &6 on the lower cam shaft 288 acting through a camfollower 518 mounted on the end of a lever arm 528. The lever arm 528 ispivoted at 275. The other end 522 of the lever 52) is bifurcated andslidably straddles a pivot block 524 (FIGS. 3, 14) mounted on pivot arm526 attached to the end of the shaft 502.

Advance and retraction of the slide 498 on the platform 500 iscontrolled by la wire threader feed cam 528 (FIG.

14) also mounted on the lower cam shaft 288. Cam follower 538 isattached at an intermediate point to the lever arm 532 which is pivotedat one end about a pin 534 held by a bracket 536 affixed to theapparatus frame. Connecting rod 538 is secured to the other end to thelever 532 and to a pin 540 aixcd to the slide 498.

4Rotation of the platform 588 about the shaft 502 is prevented by theprovision of a member 542 which depends from the platform and is guidedby arms 544, 546 aiixed to the bracket 512. In this manner vertical andhorizontal movement of the wire threader means 486 is possible duringthe production operation but rotation about the reciprocating shaft 502is prevented.

Plowz'ng mechanism The lateral wire 188 is secured to the frame `11.82at the start 122 and termination .124 of the grid winding. In theembodiment of the invention illustrated in the drawings, separatemechanisms are provided for closing the starting notch `242 andterminating notch 244 in the side rod 116 about the wire 188. Each ofthe notches is closed by plowing a portion of the external wall of thenotch over the wire as it rests in the bottom of the notch. The toolconfiguration employed in this embodiment of the invention is best seenin FIG. 28 wherein the plowing tool 548 for closing the starting notch242 is illustrated. The tool 548 is provided with an inclined surface558 and a vertical surface 552 which cooperate to perform the plowingfunction when driven against the side rod. The tool 554 for closing theterminating notch 244 is similar in configuration to the plowing tool548 but of the opposite hand (see FIG. 24). The plowing toolconfiguration employed is dependent upon the shape of the notch 242,244`formed previously by the notcning tools 246, 248, and may be variedto coincide therewith.

Referring to FIG. 3, the left or starting notch plowing tool 548 isadjustably 4secured to the end of a slide 556 carried in a slideway 558on the appartus frame. A cap 568, to which is aiiixed a pivot block 562(see FG. 14), is attached to the upper end of the slide 556. Pivot block562 is slidably straddled by the bifurcated end 564 of lever arrn 566.Lever arm 566 is pivoted at 56S on a bracket 578 secured to theapparatus frame. Cam follower 572 is mounted on the other end of thelever arm 566 and is positioned within the groove 574 of a constrainedcam 576. The cam 576 is mounted on the upper cam shaft 578. The uppercam shaft 578 is journaled in the bracket 570 and in a support 580`(FIG. l). The lower cam shaft 288 and upper cam shaft 578 are coupled bya chain drive which comprises a sprocket 582 on the lower shaft 288, asprocket 5184 on the upper shaft 578, and a chain 586 therebetween. Inthis manner the shafts 288, 578 are driven in synchronism by the gearmotor 282 and will each make one complete revolution per grid.

Referring once again to FIG. 3, the right or terminal plowing tool 554is adjustablyV secured to the end of a slide 588 carried in a slideway5950 on the apparatus frame. The upper end of slide 598 bears a cap 592to which is secured a pivot block 594 (FIG. 2). Pivot block 594 isslidably straddled by the bifurcated end 596 of a lever arm 598. Thelever arm ,598 is pivoted at 608 on the bracket 570. It has a camfollower 602 which is within the groove of constrained cam 604- mountedon the upper cam shaft 578.

The slideways 558, 5.98 may be repositioned on the apparatus frame tovary the relative position ofthe tools 548, 554 for other grid types andsizes. This adjustment may be used when the amount of change is greaterthan that which may be conveniently compensated for by individualadjustment of the tools themselves.

l Three cam stops D, E, F, have their respective cams 606, 688, 610secured to the upper cam shaft 578 intermediate the support 588 and thebracket 570. The-ir control solenoids 612, 614, 616 are mounted on theplatform 114 adjacent the cam Ishaft 578. Cam stop F comprising cam 616,solenoid 616 and frame mounted spring loaded pivot arm 618 is mostclearly seen in FIG. 2. Solenoid 612, through pivotarm 620, controls cam606 of cam stop D While solenoid 614 through its pivot arm 622 controlscam 668 of cam stop E.

A bank of timing switches 624 (not shown individually) mounted on abracket 626 are operated by the upper cam shaft 578 through sprocket 628and timing chain 630 at a one to one ratio. These timing switchescontrol portions of the machines cycl-e but their particular arrangementand construction is secondary to the consideration of the inventionherein described.

Finished grid conveyor mechanism Conveyor 632 is positioned adjacent theretracted position of the movable winding spindle 142 so that thecompleted grids will be deposited on the conveyor when stripped from thewinding mandrel 126. The conveyor belt 634 is tensioned by an idler roll636 mounted on a slide 638. Spring 640 is positioned in part within theslide 638 and reacts against the slideway 642. The slideway 642 is partof the conveyor support and guide 644 which is carried by a bracket 646.Bracket 646 which is aflixed to the apparatus frame also carries theconveyor drive motor 648. The output of the motor is delivered toconveyor through a sprocket 650, chain 652 and sprocket 654 aflixed tothe drive roll shaft 656. Drive roll 658 is affixed to the shaft 656.The operation of the conveyor is coordinated with the apparatus cycle todeliver the completed grid to a receptacle, not shown, at the rear ofthe apparatus.

Operation of the apparatus The description of the operation of theapparatus will follow a typical grid through the manufacturing process.At the start of the cycle spindle drive motor 170 is rotating at lowspeed under the control of the servo potentiometer 358 on the arrestedfeed cam shaft 334. The spindles 142, 148 are kept from rotating byde-energized cam stop A on the spindle drive shaft 166. Clutch 175 onthe drive shaft 166 is partially activated in that only a part of thefull power generated by the motor 170 is transmitted to the spindledrive shaft 166. However, sufcient force is applied through the clutchto keep the cam 183 of cam stop A against the pivoted lever ar-m 188 ofthe de-energized solenoid 185. The cam shaft drive motor 282 is alsorotating at this time. Clutch 292 allows application of partial force,by slipping engagement, to the cam shafts 28), 578 which are heldagainst rotation by cam stop D. Sufficient force is transmitted by theclutch 292 to keep the cam 666 against the pivoted arm 620 ofde-energized solenoid 612.

The winding spindle 142 is in its retracted position as is the stripperbar 238'. The position of cam stop A is adjusted on the shaft 166 sothat the winding mandrel is held with the major axis of the gridsupporting portion of the mandrel vertical as shown in FIG. 3. Theoperator threads the frame 162 onto the winding mandrel 126 by aligningthe side rods 116 with the grooves 128 and sliding the frame along themandrel until the straps 128 abut the mandrel shoulder 130 (see FIG. 8).The next step in the cycle advances the vnnding spindle 142 to theworkstation beneath the plowing tools and above the notching tools by`applying fluid pressure to the spindle moving means 195. The tapered end132 of the winding mandrel 126 enters the slot 150 in the receptor 144carried by the left spindle 148. The advance of the mandrel is stoppedwhen the end 132 is firmly seated in the receptor. The grid frame straps11S abut the shoulder 152 on the receptor (FIGS. 1l, 12) and the gridframe is thus accurately positioned. The movable spindle 142 isadditionally supported, adjacent the workstation, by the yoke 194 toprevent the deflection of the spindle and subsequent movement of themandrel as the various operations are performed on the grid frame. Asthe spindle 142 approached its most advanced position the pin 260carried by the ram 196 of the spindle moving motor 195 tripped amomentary contact limit switch 202. This limit switch causes solenoid612 of cam stop D to be energized freeing the cam shafts 28), 578 forrotation and fully activates the clutch 292 applying the force of thegear motor 282 to the shafts 280, 578. Therefore, rotation of the camshafts 280, 578 is connected (see FG. 29). Movement of the lower camshaft 280 rotates the notching cam 278 moving the notching tools 246,248 to simultaneously form the starting and terminal notches 242, 244respectively (see FIGS. 23, 24). The movement of the cam 278 istransmitted to the tool slide 254 by lever 258 which is rocked about itspivot 276. The position of the tools is adjusted to control the depth ofthe penetration of the tools into the side rod 116.

The bank of timing switches indicated generally at 624 is driven at aone to one ratio by upper cam shaft 578. As the cam shafts 280, 578rotate, the individual switches are operated in sequence. After thenotches have been made in the side rod and the notching tools have beenwithdrawn, a timing switch 624 (not shown individually) energizessolenoid 185 which releases cam stop A on the spindle drive shaft 166and de-energizes solenoid 186 operating cam stop B on the same shaft.The similar cams 183, 184 are set 180 degrees apart about the shaft 166.This allows the winding mandrel 126 to be rotated 180 degrees, asshownin FIG. 27, before the drive shaft 166 is once again arrested. Thispositions the frame 102 with the notches 242, 244 uppermost (see FIG.27) in position for the placement of the lateral wire 108. Thede-energization of solenoid 186 also operates limit switch 192 whichde-activates cam stop E on shaft 578 to arrest the rotation of the camshafts when the notched portion of cam 668 is reached.

The lateral wire feed cam 390, which is driven by the spindle driveshaft 166, is held at its zero degree or starting position byde-energized cam stop C and partially activated clutch 332. Therefore,the wire guide and clamping means 446 is positioned opposite and closeto the starting notch 242 formed in the grid frame 102. The lateral wireis clamped between the extensions 452 of the fingers or jaws 448, 450 ofthe wire guide and clamping means 446 under the contr-ol of a timingswitch (not shown individually). The wire threader lift cam 516 and wirethreader feed cam 528 cooperate to move the threader 486 to a positionwhere it may grasp the lateral wire 10) from the wire guide 446 and thenposition it in the rst notch 242 (see FIG. 29). The threader is moved tothe grasping position during the frame notching operation (see FIG. 21).As the lower cam shaft 280 rotates to perform the notching operations,the wire threader lift cam 516 raises the reciprocatable rod 562 throughthe lever arm 520. This movement raises the wire threader 486 above theframe 102 (see FIG. 26). The wire threader feed cam 528 then moves thethreader 486 across the grid frame after which the threader is loweredto the grasping position by the lift cam 516. At this time the fingers488, 490 are opened by the action of the controlling timing switch 624(not shown individually). As the threader descends the extensions 492 ofthe threader fingers 488, 490 are passed on each side of the wire 108 asit is clamped in the wire guide 446. The threader jaws 488, 490 areclosed about the wire and then the wire guide jaws 448, 45t) are opened.The opening and closing of the jaws of the threader 486 and guide 446are controlled by the timing switches 624 (not shown individually) toobtain the desired grasping and releasing sequence. At this time therotation of the cam shafts 280, 578 is arrested, as previouslydescribed, by de-energized cam stop E and the degree rotation of thenotched frame takes place.

After the frame 102 has beenrotated 180 degrees, cam stop E is energizedby a timing switch 624 (not shown individually) and the cam shafts 280,578 rotate once again (FIG. 29). The rotation of the cam shafts causesthe threader feed cam 52S and lift cam 576 to draw the lateral wire 100across the frame 102 and move it downwardly, positioning the wire 100 inthe starting notch 242. The iirst plowing tool 548 is then caused todescend from a rest position which allows clearance for movement of thethreader 486 and secures the lateral wire 100 in the notch by closingthe external wall of the notch over the wire as shown in FIG. 28. Thedescent and subsequent retraction of the plowing tool is produced by thecam 576 on the upper cam shaft 573. At this time the wire 100 extendsbetween the clamped threader jaws, the frame 102 and the wire supplymeans 106 (see FIG. 27). Solenoid 186 is then energized by a timingswitch 624 (not shown individually) releasing cam stop B so that thespindle drive shaft 166 is free to rotate. Energization of solenoid 186also operates limit switch 192 to de-energize solenoid 616 thus stoppingrotation of the cam shafts against cam stop F. Solenoid 350 is energizedfreeing cam stop C, thus allowing feed cam shaft 334 to rotate.Simultaneously, full pressure is applied to clutch 332 engaging feed camshaft 334. Operation of solenoid 350 also activates limit switch 352which permits application of full pressure to spindle clutch 175bringing the latter from drag to positive engagement. Rotation of thegrid frame causes the portion of the lateral wire 100 which was betweenthe threader 486 and the frame 102 to be severed against the side rod116 to which it has been secured. The tail of wire which extendedbetween the frame and the threader 486 remains clamped in the threaderjaws until removed later in the cycle/by the momentary operation of thejaws. Y

The speed of rotation of the spindle drive motor 170 is fully controlled-by the servo potentiometer 358 which is coupled to the feed cam shaft334 and which makes one full revolution per grid cycle. The grid windingspeed, i.e., speed of rotation of the grid frame, is controlledaccording to a trapezoidal speed versus length of grid winding curve(see FIG. 30). This has been found to produce unique results in that thewire 100 placement on the side rods 116, 117, at the start and end ofthe grid winding is more closely controlled, by reduction of vibration,in this manner. The slow starting and stopping speeds also allow the useof positive cam stops A, B to accurately position the grid frame. g

The rotation of the feed cam 390 is coupled to the rotation of thespindles 142, 148 through the geared speed reducer 318, change geartrain 324, and clutch 332. The contour of the cam 390 determines thepitch of the grid being wound. Changes in pitch may also be produced byutilizing the change gear feature.

A retarding force is applied to the drum 428 by the pivoted brake lever436, as the lateral wire 100 is drawn from the spool 426 of the wiresupply means 106. This retarding force tensions the extremely ne lateralWire 100 and also prevents backlash if the wire should break during thewinding operation. The lateral wire extends from the spool 426 of thesupply means to the frame 102 to which it is secured. It passes beneaththe felt pad 484 of the vibration damper, over the rub rail 476 andbetween the slightly opened clamping extensions 452 of the guide means446 (see FIG. 14). The wire vibration damper 478 is mechanically tunedto reduce the vertical vibrations generated in the wire as it is woundabout the alternating side rods 116, 117 of the rotating grid frame 102.At relatively low winding speeds, the frictional engagement of thetensioned lateral wire 100 and the side rods 116 is suliicient tomaintain the wire in position on the side rods. At the high windingspeeds such as those employed in winding the Icenter portion of the gridofthe present embodiment, the vibratory movement of the undamped wire isbelieved to cause the wire to shift or bounce from its proper positionon the side rods 116, 117. By tuning the vibration damper reed 480 thewire is kept from oscillating wildly and thus -is held in positionduring the high speed portion of the winding operation.

Timing cam 354 on the feed cam shaft 334 is positioned to operate limitswitch 356 as the last turn of the grid winding is wound into theterminal notch 244 on the frame 102. Limit switch 356 de-energizes camstop B accurately arresting the rotation of the slowly moving grid frame102 withthe notches 242, 244 uppermost so that the terminal notch 244may be closed about the lateral wire thus securing it to the frame. Theterminal notch 244 is closed by the right plowing tool 554. The armatureof solenoid 136 of deenergized cam stop B operates limit switch 192 whenthe stop arm 188, to which it is coupled, drops into the notch 137 inslowly rotating cam 134 on the 4spindle drive shaft 166. Limit switch102 then energizes cam stop F freeing the cam shafts 260, 576 forperformance of the last plowing operation. At this time feed cam clutch332 is disengaged and cam stop C de-energizerl and ready to stop therotation of the feed cam shaft 334 when it is returned to its zerodegree or starting position.

The wire guide jaws are operated by a timing switch 624 (not shownindividually) to cause the wire to be securely clamped between theextensions 452 of the fingers or jaws 44S, 450 before the last plowingoperation occurs but when the wire is in the terminal notch. The camshafts 280, 57S rotate to produce the plowing movement which secures thelateral wire in the terminal notch 244 by closing the external wall ofthe notch over the lateral wire. The cam shaft rotation is stopped afterthe plowing action by cam stop D. This is possible since limit switch202 which originally energized solenoid 612 is of the one-way momentarycontact type. The cam shafts 280, 578 have thus completed one revolutionand are in position for the next cycle.

After the wire 100 has been secured to the grid frame, but prior tothearresting of the cam shafts 280, 578, a timing switch 624 (not shownindividually) energizes the return motor 363 which is coupled throughoverrunning clutch 370 to the feed cam shaft 334. The overrunning clutch370 permits the unimpeded rotation of the shaft 334 by the spindle driveshaft 166 while the return motor was inoperative. The clutch 370 nowoperates to couple the return motor 368 to the shaft 334 as the motor368 operates. The shaft is rotated at a higher rate of speed by thereturn motor than when coupled to the spindle drive shaft 166. Thelateral wire 100 which is secured to the frame is clamped in the wireguide 446 at this time. The more rapid rotation of the feed cam 390which is due to the return motor 36S speed plus the depression 400 orchange in contour of the cam periphery causes the wire guide 446 to moverapidly with respect to the grid frame 102. This rapid movement raisesthe tension of the secured wire above its breaking point. The wirebreaks at its weakest point, at the outer edge of the terminal notch 244of the grid winding, adjacent the frame 102. In this way the wire issevered from the frame while retained in the guide means 446 in positionfor the next threading operation. While this method of severing thelateral wire is preferable since it requires no additional elements,other embodiments of the invention may employ cutters for severing thelateral wire 100 adjacent the grid frame 102.

The return motor 36S continues to drive the feed drive shaft 334, afterthe lateral wire has been severed, until the de-energized cam stop Carrests its rotation at the zero degree or starting position. The slipclutch 378 on the shaft 334 then permits the return motor to continuerotating until the motor is de-energized by a tim- 13 ing switch 624(not shown individually) although the shaft 334 is arrested.

Prior to the completion of the grid the stripper bar fluid motor 234, isenergized by a timing switch 624 (not shown individually) moving thestripper bar 230 into its operative position. After the lateral wire hasbeen severed a timing switch 624 (not shown individually) energizes thespindle moving means 195 to retract the winding mandrel 126 and spindle142 from the workstation. Pin 222, which is connected to the stripperpins 138, is arrested by the stripper bar 236 as the spindle 142 isretracted. Continued movement of the spindle 142 creates relativemovement between the arrested stripper pins 13S and the winding mandrel134. The

stripper pins 138 stop the movement of the completed grid as the mandrel126 is withdrawn from within the grid. The grid then drops to theconveyor 632 positioned therebeneath which delivers it to a receptacle,not shown, at the rear or" the apparatus.

Continued retraction of the spindle 142 causes pin 260 to operate aone-way momentary limit switch 294 which energizes cam stop D allowingthe spindle drive shaft 166 to rotate the spindlts 142, 148, 180 degreesuntil deenergized cam stop A is reached. Pin 26MB momentarily operateslimit switch 206 to retract the stripper bar 23d when the spindle 142has been fully retracted. The apparatus has now completed one cycle andis in position for the commencement ofthe next cycle.

The above described apparatus is capable of closely controlled highspeed production of small electrodes such as frame-type grids whichemploy extremely line lateral wire. The useful life of the toolingemployed is prolonged by attaching the lateral wire to the frame at thebeginning and termination of the grid winding. The improved windingprocess disclosed enables the wire laying operation to be performedaccurately Without variation of lateral wire position.

Although one embodiment of the invention has been shown and described,it will be apparent to those skilled in the art that various changes andmodifications may be made therein without departing from the scope ofthe invention as defined by the appended claims.

What is claimed is:

1. In an apparatus for manufacturing a grid having closely spaced turnsof lateral grid wire wound about a grid frame the combination of aWorkstation, means for rotatively supporting said grid frame, a loadingstation, means for moving 4said support means from said loading stationto said workstation, means for supplying said llateral wire, means forfeeding said lateral wire to said frame, means at said workstation forsecuring said lateral wire to said frame, means for moving said lateralwire supply means to feed said lateral wire along said frame while beingwound thereon, and means at said Workstation for securing the lateralWire to said frame at the completion of said winding operation.

2. In an apparatus for manufacturing a grid having a plurality ofclosely spaced turns of lateral grid wire wound about a grid frameformed from a pair of side rods connected by upper and lower strapspositioned adjacent the ends of said side rods and transverse to thelongitudinal axis of said side rods the combination of a workstation,means for supporting said grid frame, means for advancing said supportmeans from a loading station to said workstation, means at saidworkstation for forming a first transverse notch on a side rod and asecond transverse notch spaced therefrom along the axis of said rods,supply means for said lateral wire, means for grasping one end of saidlateral wire from said supply means and positioning said end in saidfirst mentioned notch, means for closing said notch about the end ofsaid Wire whereby said wire is secured to said side rod, means forrotating said grid support, means for moving said lateral wire supplymeans parallel to said longitudinal axis of said grid frame while saidgrid frame is rotated whereby a plurality of turns of saidv lateral Wireare applied to said grid frame, means for arresting the rotation of saidgrid support when said laterial wire is wound into said second mentionednotch, means for closing said second notch about said lateral wirewhereby said lateral wire is secured to said side rod, and means forshifting said lateral wire supply means relative to said arrested gridframe whereby said lateral wire is severed adjacent said second notch.

3. In an apparatus for manufacturing a grid having a plurality ofclosely spaced turns of lateral grid wire Wound about a grid frameformed from a pair of side rods connected by upper and lower strapspositioned adjacent the ends of said side rods and transverse to thelongitudinal axis of said side rods the combination of a workstation,means for supporting said grid frame, means for advancing said supportmeans from a loading station to said workstation, means at saidworkstation for forming a lirst transverse notch on a side rod and asecond transverse notch spaced therefrom along the axis of said rods,supply means for said lateral wire, means for grasping one end of saidlateral wire from said supply means and positioning said end in saidfirst mentioned notch, means for closing said notch about the end ofsaid wire whereby said wire is secured to said side rod, means forrotating said grid support, means for moving said lateral wire supplymeans parallel to said longitudinal axis of said grid frame While saidgrid frame is rotated whereby a plurality of turns of said lateral wireare applied to said grid frame, means for arresting the rotation of saidgrid support when said lateral wire is wound into said second mentionednotch, means for closing said second notch about said lateral wirewhereby said lateral wire is secured to said side rod, and means tosever said lateral wire adjacent said frame.

4. In an apparatus for manufacturing a grid having a plurality ofclosely spaced turns of lateral wire wound about a grid frame formedfrom a pair of side rods rigidly connected by upper and lower strapspositioned adjacent the ends of said side rods and transverse to thelongitudinal axis of said side rods the combination of a workstation,means for supporting said grid frame, means for advancing said gridsupport from a loading station to said workstation, means at saidworkstation for simultaneously forming a first and second notch in saidside rods adjacent said straps transverse to the 1ongitudinal axis ofsaid side rods and intermediate said straps, means for supplying saidlateral wire, means for grasping one end of said lateral Wire from saidsupply means and positioning said lateral wire in said first mentionednotch, means for closing said notch about said wire whereby said wire issecured to said side rod, means for rotating said grid support, meansfor shifting said lateral wire supply means parallel to the longitudinalaxis of said grid frame while said grid frame is rotated whereby aplurality of turns of said lateral wire are applied to said grid frame,means for dampening the oscillation of said lateral wire during saidwinding operation, means for arresting the rotation of said grid supportwhen said lateral wire is placed in the second mentioned notch, meansfor closing said second mentioned notch about said lateral wire wherebysaid lateral wire is secured to said side rod, means for shifting saidlateral wire supply means relative to said arrested grid frame wherebysaid lateral Wire is severed adjacent said second notch, and means forreturning said grid support to said loading station.

5. In an apparatus for manufacturing a grid having a plurality ofclosely spaced turns of lateral wire wound about a grid frame formedfrom a pair of side rods rigidly connected by upper and lower strapspositioned adjacent the ends of said side rods and transverse to thelongitudinal axis of said side rods the combination of a workstation,means for supporting said grid frame, means for alsa-esa 5 advancingsaid grid support from a loading station to said workstation, means atsaid workstation for simultaneously forming a rst and second notch insaid side rods adjacent lsaid straps transverse to the longitudinal axisof said side rods and intermediate said straps, means for supplying saidlateral wire, means for grasping one end of 4 said lateral wire fromsaid supply means and positioning said lateral Wire in said firstmentioned notch, means for closing said notch about said wire wherebysaid wire is secured to said side rod, means for rotating said gridsupport, means for shifting said lateral wire supply means paralleltothe longitudinal axis of said grid frame While said grid frame isrotated whereby a plurality of turns of said lateral wire are appliedtosaid grid frame, means for dampening the oscillation of said lateralwire during said winding operation, means for arresting the rotation ofsaid grid support when said lateral wire is placed in the secondmentioned notch, means for closing said second notch about said lateralwire whereby said lateral wire is secured to said side rod, and means tosever said lateral wire adjacent said frame.

6. In a grid winding machine for winding a helix of lateral wire about aframe, the combination of means for `supporting a grid frame on arotatively driven grid winding spindle, a carriage, a cam, means forrotating said cam at a given rate, a Vcam follower on said carriage,means for urging said follower .against said cam whereby said carriageis moved relative to said spindle, supply means for lateral wire mountedon said carriage, means for feeding said lateral wire to said frame,means for securing said lateral wire to said frame at the start of saidhelix, means for securing said lateral wire to said frame at the end ofsaid helix, means for clamping said lateral wire to said carriageintermediate said supply means and said frame, and means foraccelerating the rotation of said cam to move said carriage more rapidlyi@ whereby said clamped lateral wire is severed against said frame.

7. In a grid winding machine for winding a helix of lateral wire about agrid support the combination of means for rotating said grid support,means for supplying a continuous lateral Wire to said support, means forsecuring said lateral wire to said grid support, and means for dampeningthe oscillation of said lateral wire between said grid support and saidlateral Wire supplying means during said winding.

8. In a grid Winding machine for Winding a helix of lateral Wire about agrid support the combination of means for rotating said grid support,means for supplying a continuous lateral wire to said support, means forsecuring said lateral wire to said grid support, means for dampening theoscillation of said lateral Wire between said grid support and saidlateral wire supplying means during said winding, said oscillationdampening means comprising a lever arm having a lateral wire contactingportion against said lateral wire, said lever arm being tuned to thedampening frequency of the oscillation of said lateral wire.

References Cited by the Examiner UNITED STATES PATENTS 2,380,320 7/45 LaFrance 140-7l.5 2,778,386 1/57 Lindsay 140-71.5 2,959,367 11/60 Kuba etal 14C-71.5 2,999,300 9/61 Sandor 140--715 3,037,533 6/62 Chase 140-71.5

FOREIGN PATENTS 963,260 5 5 7 Germany.

CHARLES W. LANHAM, Primary Examiner.

RICHARD A. WAHL, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No3,191,637 June Z9, 1965 Alton L. Crosby et a1.,

It is hereby certified that error appears in the above numbered patentreqiirng correction and that the said Letters Patent should read ascorrectedbelow.

Column 3, line 56, for "132" read 102 column 5, lir 31, for "came" readcam column 7, line 61, for "501" Tea 502 line 62, for "502" read 508.column 10, line S for "connected" read commenced column 13, line 23, for"spindlts" read spindles column 14, line 4, for "lateria read lateralSigned and sealed this 7th day of December 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Atlcsting Officer Commissioner ofPatents

1. IN AN APPARATUS FOR MANUFACTURING A GRID HAVING CLOSELY SPACED TURNSOF LATERAL GRID WIRE WOUND ABOUT A GRID FRAME THE COMBINATION OF AWORKSTATION, MEANS FOR ROTATIVELY SUPPORTING SAID GRID FRAME, A LOADINGSTATION, MEANS FOR MOVING SAID SUPPORT MEANS FROM SAID LOADING STATIONTO SAID WORKSTATION, MEANS FOR SUPPLYING SAID LATERAL WIRE, MEANS FORFEEDING SAID LATERAL WIRE TO SAID FRAME, MEANS AT SAID WORKSTATION FORSECURING SAID LATERAL WIRE TO SAID FRAME, MEANS FOR MOVING SAID LATERALWIRE SUPPLY MEANS TO FEED SAID LATERAL WIRE ALONG SAID FRAME WHILE BEINGWOUND THEREON, AND MEANS AT SAID WORKSTATION FOR SECURING THE LATERALWIRE TO SAID FRAME AT THE COMPLETION OF SAID WINDING OPERATION.